David Cameron is not a man to hide his light under a bushel, as you might expect from a Prime Minister with an election due in just over a year.

There he was at Birmingham Airport last week, effusively welcoming the announcement that 8,000 new jobs would be created, principally as a result of the long-awaited runway extension, with anticipated direct links to the likes of the West Coast of America and China.

Shamelessly linking the airport jobs announcement with totally unrelated Government tax-cutting measures, the PM boomed: “The announcement of 8,000 jobs from Birmingham Airport is more great news in a week when we are cutting tax for 26 million hard-working people and taking over three million people out of income tax altogether.”

Not surprisingly, Birmingham Airport Chief Executive Paul Kehoe provided more flesh on the bones, saying: “Receiving this endorsement from the Prime Minister as our runway extension nears completion is fantastic for everyone involved in the project. Birmingham is recognised as an airport that is delivering real growth and supporting thousands of new jobs.

“The main driver for this growth is the runway extension. By 2020, based on today’s demand, Birmingham Airport is forecast to handle 15 million passengers a year, an increase of six million. This passenger growth will generate an additional 4,000 jobs on-site and a further 4,000 in the immediate supply chain.”

This is heady stuff. 8,000 new jobs would clearly be a substantial tonic to a regional economy and there’s no reason to doubt the sincerity of Mr Kehoe’s ambition. The runway extension is well under way, and will clearly open up the market for long-haul flights out of Birmingham.

But the journalistic cynic in me remains slightly sceptical. In Mr Kehoe’s own words, the 8,000 extra jobs forecast is based on an increase of six million passengers a year, quite a jump by anyone’s standards. And the airlines will still have to commit to new direct long-haul routes to the likes of LA or Beijing before anybody can board a plane.

So, however much Mr Kehoe and the Prime Minister talk up the 8,000 new jobs, and however much the rest of us would be delighted to be able to fly directly to California from Birmingham, there is a considerable amount of water to pass under the bridge before we’re all jetting off to Hollywood.

Part of the potential problem here is that politicians and business leaders are very good at talking the talk, but not always so assiduous at walking the walk. A few random examples of recent times spring to mind...

Eight years ago, in March 2006, plans were announced for Europe’s first theme park in the sky next to Millennium Point. The 650 ft high VerTiPlex was to be the first of its kind in Europe.

The £95 million development was hailed as a futuristic tourist attraction which would be Birmingham’s tallest building, with a selection of theme park rides and a restaurant at the top.

Developers forecast that the tower would attract one million visitors in the first 12 months. The only problem was it never happened, and the land on which it was to have stood was quietly put to other uses.

In November 2000, detailed plans were unveiled for a £100 million all-seater ‘Millennium Stadium’ on a site at the NEC, complete with sliding roof and room for 50,000 spectators.

Proposals drawn up by Birmingham construction specialists Wakemans and local architects Temple Cox Nicholls envisaged a huge sports arena capable of hosting indoor and outdoor international events, alongside a range of nightclubs and bars. But, just like the theme park in the sky, it never happened.

At least the V Building, an ‘iconic’ – what isn’t ‘iconic’ these days? – 50-floor building which was to become Britain’s tallest all-residential tower earmarked for the old ATV Studios site at Arena Central off Broad Street got as far as planning approval.

Developers Dandara said back in October 2007: “Scheduled for completion in 2013, this is a stunning scheme...soaring to over 150 metres...it sparkles and shines with reflective glass and warm grey metal.” Architect Eric Kuhne said: “The V Building will be a new skyline element defining Birmingham’s renaissance as a 21st century city, standing testimony to the vision and leadership of the private and public partnership in Birmingham.” Fine words, but the V Building, to this day, remains as elusive as the Dodo on Broad Street.

In March 2004, plans were unveiled for a new £80 million headquarters for Birmingham’s biggest business organisation, the Chamber of Commerce.

The Chamber’s 40-year-old block was to be demolished and new headquarters on the corner of Harborne Road and Highfield Road built, providing 228,000 sq ft of ‘quality space,’ with 9,000 sq ft of restaurants and bars on the ground floor. It never happened – and the Chamber is still in its old home.

There is no direct link between the aforementioned projects that never came to pass and Birmingham Airport’s categoric promise of 8,000 extra jobs so enthusiastically endorsed by the Prime Minister.

Conversely, more than a little caution should habitually be exercised whenever we see a vote-hungry politician jumping on a business bandwagon with the promise of jam tomorrow. In some cases, tomorrow never comes...